Postoperative Venous Thromboembolism In Patients Research Articles

Apixaban versus enoxaparin to prevent venous thromboembolism in postoperative patients with gynecologic cancers at an urban academic medical center

Apixaban versus enoxaparin to prevent venous thromboembolism in postoperative patients with gynecologic cancers at an urban academic medical center

Development of Machine Learning Algorithms for Predicting Preoperative and Postoperative venous Thromboembolism in Patients Undergoing Surgery for Spinal Metastasis

Objective: This study aims to develop and compare machine learning models (MLMs) for predicting venous thromboembolism (VTE) in patients undergoing surgery for spinal metastasis. The study evaluates the predictive capabilities of MLMs for preoperative and postoperative VTE within different time frames. Materials and Methods: A total of 334 patients undergoing surgery for spinal metastasis were included, with a mean age of 57.6 years and 57.2% being male. The investigation assessed postoperative VTE prevalence within 30 and 90 days, with pulmonary embolism (PE) and deep vein thrombosis (DVT) rates at 20% and 80%, respectively. Key patient-related factors—age, body mass index, preoperative ambulatory status, albumin level, hemoglobin level, partial thromboplastin time, and operative time—were considered potential predictors of VTE. Results: The postoperative VTE prevalence was 8.98% within 30 days and 13.47% within 90 days. Age, body mass index, preoperative ambulatory status, albumin level, hemoglobin level, partial thromboplastin time, and operative time emerged as significant VTE predictors. The gradient boosted tree algorithm was the best-performing MLM for predicting VTE within 90 days, with AUC values of 0.77 preoperatively and 0.71 postoperatively. For predicting VTE within 30 days, the support vector machine model was most effective, with AUCs of 0.72 preoperatively and 0.68 postoperatively. Conclusion: Predictive analytics and MLMs effectively predict preoperative and postoperative VTE in patients undergoing surgery for spinal metastasis. Identified key factors and MLM performance metrics offer valuable insights for risk assessment and preventive measures in this patient population.

Thromboprophylaxis to prevent venous thromboembolism in postoperative patients

Thromboprophylaxis to prevent venous thromboembolism in postoperative patients

Post-operative venous thromboembolism in patients after extracranial otologic surgery: A case series

ObjectiveThis study aimed to report 9 venous thromboembolism (VTE) cases after extracranial otologic surgery and analyze the potential risk factors. Study designCase series. SettingSingle tertiary-level academic center. MethodsTotally, 9 cases of VTE were identified among adults who underwent extracranial otologic surgery at our hospital from January 2018 to December 2020. Caprini risk scores were calculated, and comprehensive preoperative, operative, and postoperative clinical data within 14 days were collected to assess the evidence of VTE. ResultsThe median age of 9 patients was 64 years old. Among them, 7 (77.8%) patients presented with intramuscular vein thrombosis, 1 (11.1%) patient had deep vein thrombosis, and 1 (11.1%) patient experienced pulmonary embolism. Preoperatively, 8 (88.9%) patients had low or middle Caprini risk scores (≤4) with an average of 2.67 ± 0.47 points. The average Caprini scores for all patients were 4.44 ± 0.35 on postoperative day (POD)1 and 5.67 ± 0.64 on POD14. D-dimer levels were collected, indicating an average of 0.55 ± 0.17 mg/FEU preoperatively, 8.53 ± 3.94 mg/FEU at day 1, and 3.76 ± 0.45 mg/FEU at POD14. In postoperative period, 7 (77.8%) patients experienced vertigo/dizziness and/or head immobility/bed rest. ConclusionThe present study highlighted that patients with low- and middle-risk of VTE undergoing otologic surgery should be also vigilant about postoperative VTE. Vertigo/dizziness and/or head immobility/bed rest in postoperative period should be considered as minor risk factors for developing VTE in patients undergoing extracranial otologic surgery. Conducting perioperative assessments, including Caprini risk score evaluation, D-dimer testing, and venous ultrasound of lower extremities, is recommended to ensure patients’ safety.

Effect of a Self-instructional Module on Clinical Nurses’ Knowledge and Practice Regarding Prevention of Venous Thromboembolism in Post-operative Patients

Abstract This pre-experimental study was done to assess the effect of a self-instructional module on clinical nurses’ knowledge and practice regarding the prevention of venous thromboembolism (VTE) in post-operative patients. The sample consists of 30 clinical nurses working in post-operative ICUs selected by purposive sampling technique. The tools used were a self-administered structured questionnaire on socio-demographic data and knowledge and an observation checklist on practice regarding the prevention of VTE. The study findings revealed that there was a significant difference between the pre-test and post-test knowledge and practice scores as the mean knowledge score of the post-test (16.93 ± 2.82) is higher than the pre-test score (13.70 ± 3.35) and the mean practice score of post-test (3.06 ± 1.17) is higher than the pre-test score (2.16 ± 0.74). There was a weak positive correlation between knowledge and practice scores (r = 0.08). The study findings also showed that there was no significant association between the pre-test level of knowledge and practice with selected demographic variables such as age, gender, qualification, total years of experience, previous knowledge on VTE and source of information. It can be concluded that the self-instructional module is effective in improving the knowledge and practice of clinical nurses in the prevention of VTE.

Effect of venous foot pump intervention on prevention of venous thromboembolism in patients with major orthopedic surgery: a systematic review and meta-analysis.

Venous thromboembolism (VTE) is a common complication after major orthopedic surgery. The venous foot pump (VFP) is an effective mechanical preventive measure against VTE in patients. However, the differences in effectiveness based on varying usage times of VFP remain unclear. To explore the effectiveness of VFP with different usage times in preventing VTE in patients undergoing major orthopedic surgery. Nine databases (PubMed, Web of Science, CINAHL, Embase, Cochrane Library, CBM, VIP, CNKI, and Wanfang) were searched to identify randomized controlled trials (RCTs) evaluating VFP interventions for VTE prevention in major orthopedic surgery patients. The risk of bias in each study was assessed using the Cochrane Collaboration tool. Meta-analysis was conducted using RevMan 5.3. A total of 36 RCTs involving 3,791 patients undergoing major orthopedic surgery were included. Meta-analysis revealed significant differences in VTE incidence between the VFP and blank control groups (RR = 0.27, 95% confidence interval CI: 0.19-0.38, P < 0.001) and between the VFP plus chemoprophylaxis and chemoprophylaxis alone groups (RR 0.39, 95% CI: 0.29-0.53, P < 0.001). However, no statistically significant difference was observed between the VFP and the LMWH groups (RR = 0.93, 95% CI: 0.54-1.61, P = 0.8). Subgroup analysis showed no significant difference in effectiveness based on different VFP usage durations (VFP vs. Blank: Chi-square = 0.54, P = 0.46, I2 = 0%; VFP Plus chemoprophylaxis vs. chemoprophylaxis alone: Chi-square = 1.93, P = 0.86, I2 = 0%). The current evidence indicates that VFP significantly reduces the incidence of postoperative VTE in patients undergoing major orthopedic surgery. VFP can be considered an add-on strategy to LMWH for patients at low risk of bleeding and an alternative strategy to LMWH in patients at high risk of bleeding. This study found no significant difference in effectiveness between various VFP usage interventions. Future research should focus on economic cost-effectiveness and patient acceptance to help policymakers determine the most efficient usage duration, providing practical guidance for thromboprophylaxis.

Neoadjuvant Chemotherapy is Associated with Increased Risk of Postoperative DVT After Distal Pancreatectomy for Pancreatic Adenocarcinoma: a NSQIP Analysis.

Venous thromboembolism (VTE) remains a persistent source of postoperative morbidity despite prevention and mitigation efforts. Cancer, surgery, and chemotherapy are known risk factors for VTE. Existing literature suggests that neoadjuvant therapy (NAT) may contribute to increased VTE risk in the postoperative period, but few authors specifically examine this relationship in distal pancreatic adenocarcinoma (PDAC). In this study, we analyze the association of NAT and postoperative VTE in patients who underwent distal pancreatectomy (DP) for PDAC. Using the American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) database, we analyzed the Procedure Targeted files for pancreatectomy from 2014 to 2020. Adults with PDAC who underwent DP were grouped by receipt of NAT. The primary outcome was the rate of deep venous thrombosis (DVT) and the secondary outcome was the rate of pulmonary embolism (PE). We performed univariate and multivariate logistic regression analysis to determine risk factors associated with postoperative DVT. There were 4327 patients with PDAC who underwent DP. Of these, 1414 (32.7%) had NAT. Receipt of NAT was significantly associated with postoperative DVT requiring therapy (3.5% vs. 2.3%, p = 0.02), but was not associated with PE (p = 0.42). On MVA, NAT was associated with a 73% greater chance of developing postoperative DVT [odds ratio (OR) 1.73, 95% CI 1.18-2.55]. Patients who receive NAT prior to DP for PDAC are 73% more likely to develop postoperative DVT compared with upfront resection. As NAT becomes more commonplace, these high-risk patients should be prioritized for guideline-recommended extended duration prophylaxis.

The impact of frailty evaluation on the risk of venous thromboembolism in patients with hip fracture following surgery: a meta-analysis.

Frailty has been associated with a higher incidence of overall postoperative complications and mortality. However, the influence of frailty on the risk of venous thromboembolism (VTE) in patients with hip fracture following surgery remains unclear. We performed a meta-analysis to systematically evaluate the above association. PubMed, Embase, Cochrane Library, Wanfang and CNKI were searched for relevant observational studies comparing the incidence of postoperative VTE in patients of hip fracture with and without frailty. Data collection, literature searching, and statistical analysis were conducted independently by two authors. Using a heterogeneity-incorporating random-effects model, the results were pooled. In this meta-analysis, 9509 patients from nine cohort studies were included. Pooled results showed that compared to those without frailty, patients with frailty at admission had a higher incidence of postoperative VTE (odds ratio [OR]: 2.59, 95% confidence interval [CI]: 1.25-5.39, p = 0.01; I2 = 66%). Subgroup analysis suggested the association between frailty and postoperative VTE was more remarkable in studies of patients with frailty prevalence < 50% (OR 6.28, 95% CI 3.31-11.90, p < 0.001; I2 = 8%) as compared to those ≥ 50% (OR 1.30, 95% CI 0.80-2.11, p = 0.28; I2 = 0%; p for subgroup difference < 0.001). Further meta-analyses showed that frailty at baseline was associated with a higher incidence of deep venous thrombosis (OR 3.15, 95% CI 1.33-7.47, p = 0.009; I2 = 59%), but not pulmonary embolism (OR 1.13, 95% CI 0.59-2.16, p = 0.72; I2 = 0%). Frailty is associated with a higher incidence of postoperative VTE in patients with hip fracture.

Incidence, risk factors, and outcomes of venous thromboembolism in patients undergoing surgery for retroperitoneal tumors: A propensity-matched retrospective cohort study.

Venous thromboembolism (VTE) is a common postoperative complication; however, incidence and risk stratification of postoperative VTE in patients with retroperitoneal tumor remains unclear. We aim to quantify incidence, identify risk factors, and determine outcomes of VTE in patients undergoing retroperitoneal tumor surgery. We retrospectively reviewed characteristics, perioperative outcomes, and overall survival (OS) of patients (VTE and non-VTE) who underwent retroperitoneal tumor surgery between 2015 and 2020. Perioperative and oncologic outcomes were compared using propensity-matching and Cox analyses. Of 1223 patients with retroperitoneal tumor surgery, 2.1% had VTE. Age (odds ratio [OR] 1.140, 95% confidence interval [CI] 1.053-1.239, P=0.004), recurrence (OR 1.851, 95% CI 1.241-2.761, P=0.003), and vascular resection (OR 2.036, 95% CI 1.054-3.934, P=0.034) were independent risk factors, with significant between-group differences regarding age, recurrence, sarcoma, organ resection, vascular resection, and operation time. No between-group differences in 30-day all-cause mortality (8% vs. 4%, OR 0.657, 95% CI 0.375-1.151, P=0.427) and major complications (12% vs. 8%, OR 0.775, 95% CI 0.483-1.244, P=0.572) were observed. Mean hospitalization duration (20.1 vs. 22.9d, OR 1.153, 95% CI 1.022-1.386, P=0.033) and ICU stay (3.2 vs. 5.5d, OR 1.193, 95% CI 1.034-1.347, P=0.012) were shorter in non-VTE versus VTE, respectively, with inferior OS (hazard ratio [HR] 2.090, 95% CI 1.014-4.308, P=0.046) in VTE. Age, recurrence, and vascular resection are positively associated with VTE, which is associated with inferior OS.

(035) Risk of Post-Operative Venous Thromboembolism in Patients Undergoing Gender Affirming Surgery: An Assessment of 1,731 Patients

Abstract Introduction Venous thromboembolism (VTE) is a source of significant morbidity and mortality in the post-operative setting. However, poor follow up and the ability for patients to present to other hospital systems for post-operative care, have made assessment of the incidence of post-operative VTE difficult. As a result, previous attempts to assess VTE risk following gender affirming surgery have been limited to small volume, single institution studies. It has been hypothesized that patients undergoing gender affirming surgery may be at increased risk of post-operative VTE given the concomitant use of hormone therapy. Objective To assess the risk of venous thromboembolism and associated risk factors following feminizing and masculinizing gender affirming surgery. Methods Using IBM MarketScan, a commercial claims database, patients undergoing feminizing and masculinizing surgery were identified using Current Procedural Terminology (CPT), ICD-9, and ICD-10 procedure codes between 2011 and 2020. ICD-9 and ICD-10 codes were used to identify healthcare visits associated with lower extremity deep vein thrombosis (DVT) and pulmonary embolism (PE) within 90-days of surgery. Covariates including diabetes, peripheral vascular disease, cardiovascular disease, hypertension, varicose veins, hypercoagulable state, smoking history, and prior VTE were assessed. Given the small cohort size of men undergoing masculinizing surgery, descriptive statistics, including the 90-day incidence, were performed. In patients undergoing feminizing surgery, descriptive and univariate statistics were performed including Kruskal-Wallis tests (continuous variables) or Chi-squared/Fischer’s exact tests (categorical variables). Results 1,731 patients underwent feminizing surgery (1,588) or masculinizing (143) surgery between 2011 and 2020 with a median age (interquartile range) of 34 years (22, 53) and 35 years (26, 46), respectively. A history of DVT or PE events prior to gender affirming surgery was identified in 1.07% (feminizing) and 0.7% (masculinizing). DVT or PE events within 90-days following feminizing surgery and masculinizing surgery occurred in 1.07% and 0.7%, respectively. On univariable analysis, increasing age (p&amp;lt;0.001), bladder cancer (p&amp;lt;0.001), prior cystoprostatectomy (p=0.001), diabetes (p=0.007), cardiovascular disease (p&amp;lt;0.001), hypertension (p=0.04), prior DVT (p&amp;lt;0.001), and prior PE (p&amp;lt;0.001) were associated with increased likelihood of post-operative VTE in patients undergoing feminizing gender affirming surgery. Conclusions In a cohort of patients undergoing gender affirming surgery, the risk of post-operative VTE was low with 1.07% (feminizing) and 0.7% (masculinizing) of patients developing a VTE event within 90 days of surgery. In patients undergoing feminizing gender affirming surgery, increasing age, bladder cancer, cystoprostatectomy, diabetes, cardiovascular disease, hypertension, prior DVT, and prior PE were associated with an increased likelihood of developing a postoperative DVT or PE. Disclosure Any of the authors act as a consultant, employee or shareholder of an industry for: Cooper Medical, Boston Scientific, Acerus, Coloplast, Turtle Health, Maximus, FirmTech, StreamDx, Inherent Bioscience.

Ten-Year Multicenter Retrospective Study Utilizing Machine Learning Algorithms to Identify Patients at High Risk of Venous Thromboembolism After Radical Gastrectomy.

This study aims to construct a machine learning model that can recognize preoperative, intraoperative, and postoperative high-risk indicators and predict the onset of venous thromboembolism (VTE) in patients. A total of 1239 patients diagnosed with gastric cancer were enrolled in this retrospective study, among whom 107 patients developed VTE after surgery. We collected 42 characteristic variables of gastric cancer patients from the database of Wuxi People's Hospital and Wuxi Second People's Hospital between 2010 and 2020, including patients' demographic characteristics, chronic medical history, laboratory test characteristics, surgical information, and patients' postoperative conditions. Four machine learning algorithms, namely, extreme gradient boosting (XGBoost), random forest (RF), support vector machine (SVM), and k-nearest neighbor (KNN), were employed to develop predictive models. We also utilized Shapley additive explanation (SHAP) for model interpretation and evaluated the models using k-fold cross-validation, receiver operating characteristic (ROC) curves, calibration curves, decision curve analysis (DCA), and external validation metrics. The XGBoost algorithm demonstrated superior performance compared to the other three prediction models. The area under the curve (AUC) value for XGBoost was 0.989 in the training set and 0.912 in the validation set, indicating high prediction accuracy. Furthermore, the AUC value of the external validation set was 0.85, signifying good extrapolation of the XGBoost prediction model. The results of SHAP analysis revealed that several factors, including higher body mass index (BMI), history of adjuvant radiotherapy and chemotherapy, T-stage of the tumor, lymph node metastasis, central venous catheter use, high intraoperative bleeding, and long operative time, were significantly associated with postoperative VTE. The machine learning algorithm XGBoost derived from this study enables the development of a predictive model for postoperative VTE in patients after radical gastrectomy, thereby assisting clinicians in making informed clinical decisions.

Varicose veins as a risk factor for venous thromboembolism in arthroplasty patients: Meta-analysis.

A meta-analysis to determine if patients with varicose veins are at an increased risk of venous thromboembolism (VTE) when undergoing major lower limb arthroplasty. Medline, Embase, and Cochrane Library databases were searched using appropriate terms for studies that reported post-operative VTE in patients who had lower limb arthroplasty with any history of varicose veins. Methodological quality of included studies was quantified using the Risk of Bias (ROB) assessment tools. Findings were reported using the meta-analysis of observational studies in epidemiology (MOOSE) checklist. A total of 129 studies were identified with 11 observational studies being eligible for inclusion. This consisted of 265,194 patients who underwent lower limb arthroplasty, 2188 of which had pre-existing varicose veins. Overall, VTE occurred in 1845 patients, and 122 cases had varicose veins present at time of arthroplasty. Meta-analysis indicates that patients undergoing lower limb arthroplasty with varicose veins are at increased risk of having a VTE, OR 2.37, 95% CI 1.54-3.63, (p < 0.001). One study evaluated if previous varicose veins surgery influenced the risk of VTE in arthroplasty patients, OR 0.96 (95% CI 0.7-1.28), p = 0.429. Varicose veins and lower limb arthroplasty are known independent risk factors for VTE. There is a paucity of data regarding the risk of VTE in patients undergoing lower limb arthroplasty who have co-existing varicose veins. This meta-analysis shows that patients with varicose veins are at an increased risk of VTE when undergoing major lower limb arthroplasty. Further studies are required in order to determine if such patients should undergo varicose vein surgery before undertaking major lower limb joint replacement.

Risk Factor Analysis of Postoperative Venous Thromboembolism in Patients After Thoracoscopic Lobectomy.

To analyze independent risk factors for postoperative venous thromboembolism (VTE) in patients after thoracoscopic lobectomy and establish a risk model for predicting thrombosis. We selected 135 patients who underwent thoracoscopic lobectomy and assigned them to a VTE group (n = 31) and a non-VTE group (n = 104) according to the presence or absence of postoperative VTE. Univariate and multivariate logistic regression models were built to identify independent risk factors for postoperative thrombosis. A nomogram to predict the risk of thrombosis was generated, with the predictive performance of the model being evaluated by plotting calibration curve and the receiver operating characteristic (ROC) curve. D-dimer on the first postoperative day and Caprini scores were independent high-risk factors for VTE after thoracoscopic lobectomy as revealed by univariate and multivariate logistic regression analyses (p < .05). The nomogram was evaluated, and the fitting degree of calibration curve indicated good accuracy of the model in predicting thrombosis. The area under the curve (AUC) value was 0.8654, suggesting favorable diagnostic efficacy of the model. The D-dimer on the first postoperative day and Caprini scores were independent risk factors for VTE after thoracoscopic lobectomy. The nomogram that was generated to predict the risk of thrombosis had good accuracy and diagnostic efficacy, which can guide individual risk assessment and management decisions in clinical practice.

Development and validation of a nomogram to assess postoperative venous thromboembolism risk in patients with stage IA non-small cell lung cancer.

Venous thromboembolism (VTE) is a common postoperative complication in patients with lung cancer that seriously affects prognosis and quality of life. At present, the detection rate of patients with early-stage lung cancer is increasing, but there are few studies on the risk factors for postoperative venous thromboembolism (VTE) in patients with stage IA non-small cell lung cancer (NSCLC). This study aimed to establish a nomogram for predicting the probability of postoperative VTE risk in patients with stage IA NSCLC. The clinical data of 452 patients with stage IA NSCLC from January 2017 to January 2022 in our center were retrospectively analyzed and randomly divided into a training set and a validation set at a ratio of 7:3. Independent risk factors were identified by univariate and multivariate logistic regression analyses, and a nomogram was established based on the results and internally validated. The predictive power of the nomogram was evaluated by receiver operating characteristic curve (ROC), calibration curve, and decision curve analysis (DCA). The nomogram prediction model included three risk factors: age, preoperative D-dimer, and intermuscular vein dilatation. The areas under the ROC curve of this predictive model were 0.832 (95% CI: 0.732-0.924) and 0.791 (95% CI: 0.668-0.930) in the training and validation sets, respectively, showing good discriminative power. In addition, the probability of postoperative VTE occurrence predicted by the nomogram was consistent with the actual occurrence probability. In the decision curve, the nomogram model had a better net clinical benefit at a threshold probability of 5%-90%. This study is the first to develop a nomogram for predicting the risk of postoperative VTE in patients with stage IA NSCLC; this nomogram can accurately and intuitively evaluate the probability of VTE in these patients and help clinicians make decisions on prevention and treatment.

Venous Thromboembolism Following Major Abdominal Surgery for Cancer: A Guide for the Surgical Intern.

Venous thromboembolism (VTE) is a term used to compositely describe deep vein thrombosis (DVT) and pulmonary embolism (PE). Overall, the incidence of VTE after major abdominal and pelvic surgery has been reported to be between 10% and 40%. The aim of this study is to estimate the incidence of post-operative VTE in patients undergoing major abdominal surgery for cancer, to identify risk factors associated with VTE, and to assess available thromboprophylaxis tools. A Medline and Cochrane literature search from database inception until February 1st, 2021 was performed according to the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) guidelines. Thirty-one studies met our eligibility criteria and were included in the current review. In total, 435,492 patients were identified and the overall incidence of VTE was 2.19% (95% CI: 1.82-2.38). Τhe following risk factors were associated with VTE: smoking, advanced age (>70 years), a history of diabetes mellitus, American Society of Anesthesiologists' (ASA) classification of Physical Health class III or IV, a history of cardiovascular or pulmonary disease, a history of DVT or PE, elevated plasma fibrinogen level, c-reactive protein (CRP) level, cancer stage III or IV, postoperative acute respiratory distress syndrome (ARDS), prolonged postoperative hospital stay, previous steroid use, history of Inflammatory Bowel Disease (IBD), heart failure and neoadjuvant and adjuvant chemotherapy. VTE remains an important complication after major abdominal surgery for cancer and seems to increase mortality rates.

Readmissions From Venous Thromboembolism After Complex Cancer Surgery

Venous thromboembolism (VTE) is a major cause of preventable morbidity and mortality after cancer surgery. Venous thromboembolism events that are significant enough to require hospital readmission are potentially life threatening, yet data regarding the frequency of these events beyond the 30-day postoperative period remain limited. To determine the rates, outcomes, and predictive factors of readmissions owing to VTE up to 180 days after complex cancer operations, using a national data set. A retrospective cohort study of the 2016 Nationwide Readmissions Database was performed to study adult patients readmitted with a primary VTE diagnosis. Data obtained from 197 510 visits for 126 104 patients were analyzed. This was a multicenter, population-based, nationally representative study of patients who underwent a complex cancer operation (defined as cystectomy, colectomy, esophagectomy, gastrectomy, liver/biliary resection, lung/bronchus resection, pancreatectomy, proctectomy, prostatectomy, or hysterectomy) from January 1 through September 30, 2016, for a corresponding cancer diagnosis. Readmission with a primary diagnosis of VTE. Proportion of 30-, 90-, and 180-day VTE readmissions after complex cancer surgery, factors associated with readmissions, and outcomes observed during readmission visit, including mortality, length of stay, hospital cost, and readmission to index vs nonindex hospital. For the 126 104 patients included in the study, 30-, 90-, and 180-day VTE-associated readmission rates were 0.6% (767 patients), 1.1% (1331 patients), and 1.7% (1449 of 83 337 patients), respectively. A majority of patients were men (58.7%), and the mean age was 65 years (SD, 11.5 years). For the 1331 patients readmitted for VTE within 90 days, 456 initial readmissions (34.3%) were to a different hospital than the index surgery hospital, median length of stay was 5 days (IQR, 3-7 days), median cost was $8102 (IQR, $5311-$10 982), and 122 patients died (9.2%). Independent factors associated with readmission included type of operation, scores for severity and risk of mortality, age of 75 to 84 years (odds ratio [OR], 1.30; 95% CI, 1.02-1.78), female sex (OR, 1.23; 95% CI, 1.11-1.37), nonelective index admission (OR, 1.31; 95% CI, 1.03-1.68), higher number of comorbidities (OR, 1.30; 95% CI, 1.06-1.60), and experiencing a major postoperative complication during the index admission (OR, 2.08; 95% CI, 1.85-2.33). In this cohort study, VTE-related readmissions after complex cancer surgery continued to increase well beyond 30 days after surgery. Quality improvement efforts to decrease the burden of VTE in postoperative patients should measure and account for these late VTE-related readmissions.

A nomogram model can predict the risk of venous thromboembolism in postoperative patients with gynecological malignancies.

To explore independent factors influencing the risk of lower extremity deep vein thrombosis during the postoperative period in patients with gynecological malignancies by constructing a predictive model. In our study, we collected 573 patients with gynecological malignancies in the postoperative period between September 2016 and September 2020, who were divided into a modeling (n=402) and verification group (n=171) according to a ratio of 7:3. Univariate and multivariate regression analyses were used to determine independent factors influencing deep vein thrombosis (DVT). A nomogram model was created and a risk score was calculated. Multivariate regression analysis showed that the independent factors affecting DVT among these patients included age, hyperlipidemia, abnormal uterine bleeding, degree of anemia, D-dimer, operation time, and intraoperative blood loss. By incorporating these factors into a nomogram, we determined that the C-index and calibration curve of the two groups both showed that the model distinguishes and fits well. Further comparing between the high- and low-risk groups, we found that the model has favorable predictive performance. The predictive nomogram for the risk of DVT in patients with gynecological malignancies in the postoperative period demonstrated good calibration and recognition accuracy. Further independent research is necessary to verify our results.

Analysis of incidence and risk factors for postoperative venous thromboembolism in patients with stageⅠ a non-small-cell lung cancer

Objective: To analyze the incidence and risk factors for postoperative venous thromboembolism(VTE) in patients with stage Ⅰa non-small-cell lung cancer(NSCLC), so as to find evidence for further research of prophylactic anticoagulation. Methods: A total of 132 patients with stage Ⅰa NSCLC, 42 males and 90 females aged from 26 to 79 years with an average of (57±10) years, were retrospectively included in this study. All of them underwent surgical treatment at the Department of Thoracic Surgery of Beijing Chaoyang Hospital Affiliated with Capital Medical University from January 2017 to October 2020. A lower extremity venous ultrasound was performed before and after the operation. Participants were divided into VTE group (n=11) or non-VTE group (n=121) according to whether or not VTE occurred after operation. The surgical conditions, test indicators, imaging information, pathology information were compared between the two groups. Logistic regression analysis was performed to test the associations of VET with putative risks factors in which significant differences were observed. The independent risk factors of VET were determined by this way. Results: Postoperative VTE occurred in 11 cases (8.3%), including 10 cases (90.9%) of deep vein thrombosis (DVT) of lower limbs and 1 case (9.1%) of DVT complicated with pulmonary embolism (PE). The mean age of Patients in the VTE group was older than that in non-VTE Group ((65±9) years vs (57±10) years, P=0.009). On the fifth day after operation, patients in both groups had significantly higher D-dimer level compared with that before operation (3.18(1.55, 5.15) vs 1.54(1.09, 2.57); 2.66(1.17, 4.65) vs 1.34(0.78, 2.04))(both P<0.05). The value of neuron-specific enolase (NSE) and the number of lymph nodes removed during the operation in the VTE group were significantly higher than those in the non-VTE group ((21.54±12.37) vs (14.72±5.75); (19.7±8.2) vs (13.0±7.9)) (both P<0.05). There was no statistically significant difference in the approach of surgery, imaging features (tumor location, vascular cluster signs, etc.), and pathological information (pathological types, etc.) (all P>0.05). The logistic regression analysis showed that the number of lymph nodes removed during the operation was an independent risk factor related to the occurrence of VTE (OR=1.306, 95%CI:1.000-1.600,P<0.05). Conclusions: The incidence of postoperative VTE in patients with stage Ⅰa NSCLC is approximately 8.3%. The number of lymph nodes removed during the operation may be an independent risk factor for postoperative VTE in patients with stage Ⅰa NSCLC.

Impact of routine preoperative sonographic screening with early intervention for deep venous thrombosis in lower extremities on preventing postoperative venous thromboembolism inpatients with gastric cancer scheduled for minimally invasive surgery.

This study aimed to investigate the clinical efficacy of lower-extremity ultrasonography screening with early intervention for deep venous thrombosis (DVT) on the incidence of venous thromboembolism (VTE) after minimally invasive surgery (MIS) for gastric cancer (GC). Between January 2012 and December 2019, 1070 patients were diagnosed with both clinical and pathological stage I-III GC and underwent MIS at our institution. Routine ultrasonographic screening for DVT in lower extremities is performed before MIS. Patients diagnosed with DVT were preoperatively administered anticoagulant therapy. Enoxaparin was routinely administrated after surgery irrespective of the presence of DVT. The incidence of postoperative symptomatic VTE was examined retrospectively. A total of 74 (6.9%) patients were preoperatively diagnosed with DVT. Multivariate analyses revealed that age > 70years (p = 0.015), female sex (p < 0.001), and positive serum D-dimer test (p < 0.001) were significant and independent risk factors for preoperative DVT. The incidence of symptomatic postoperative VTE was 1 (0.09%); symptomatic VTE developed in one patient among patients without DVT, whereas no patient with DVT developed VTE. Preoperative DVT screening using lower-extremity ultrasonography followed by preoperative anticoagulant therapy should be considered as a useful strategy to safely perform MIS for GC without increasing the incidence of VTE.

Postoperative venous thromboembolism in gynecologic oncology patients undergoing minimally invasive surgery: does modality matter?

<h3>Objectives:</h3> Minimally invasive surgery (MIS) is increasingly utilized for gynecologic cancers. While rates of venous thromboembolism (VTE) after MIS are low overall, risk factors such as malignancy and prior pelvic surgery may increase risk of perioperative VTE. Various guidelines exist regarding extended chemoprophylaxis with low molecular weight heparin (LMWH) for VTE prevention. Our objective was to determine incidence of 30-day postoperative VTE in patients undergoing MIS for gynecologic malignancies and to determine differences in the incidence of VTE by MIS modality. <h3>Methods:</h3> We collected demographic and perioperative variables for all patients undergoing MIS (robot-assisted, multi-port laparoscopy, single-port laparoscopy) for gynecologic cancers between January 2014 and December 2018. Patients <18 years, with benign pathology, or on preoperative anticoagulation were excluded. Logistic regression, Chi-square, Fisher's exact test, and one-way ANOVA were performed to determine risk factors related to VTE occurrence. <h3>Results:</h3> We identified 818 patients who underwent MIS (median age 61, 97% non-Hispanic White, mean BMI 34 kg/m²). Most had Stage I disease (81.4%) and uterine cancer (81.6%). 99.9% received intraoperative unfractionated heparin (UFH) and 96.6% received immediate postoperative UFH. Three VTE events occurred within 30 days following surgery (0.3%). Twelve patients received extended chemoprophylaxis with LMWH (1.5%); 11 patients received a 28-day course while one patient received a 14-day course. VTE was diagnosed in a total of 17 patients within 18 months of surgery (2%, median time to VTE 12 months). Of those diagnosed with VTE, 11 patients underwent robot-assisted laparoscopy, 4 patients underwent multi-port laparoscopy and 2 patients underwent single-port laparoscopy. Incidence of VTE did not differ between MIS modalities (<i>p</i>=0.6). Patients with Stage III disease (<i>p</i><0.001) and longer operative time (<i>p</i>=0.04) were more likely to experience postoperative VTE. Age, smoking status, BMI, and cancer type were not significant risk factors for postoperative VTE. <h3>Conclusions:</h3> The incidence of postoperative VTE in patients with gynecologic cancers undergoing MIS is low and does not differ by modality. Extended chemoprophylaxis is unlikely to be beneficial in patients with gynecologic malignancies undergoing MIS procedures.